A worldwide shortage of radioactive isotopes that enable life-saving medical scans may have already begun to raise healthcare costs and complicate patient care.

The medical isotopes represent tiny amounts of short-lived radioactive substances that get injected into patients. They then congregate within bone or other tissues, and show up as lit areas in medical scans. That method enables 20 million medical scans and other treatments — such as targeting cancer cells for destruction — each year.

More than 50,000 patients in the United States receive such diagnostic or therapeutic procedures every day — especially those with heart problems or cancer. But the recent shortages have forced physicians to begin cutting back on the procedures.

"There has been some move away from nuclear medicine procedures to other imaging technologies that involve more radiation to the patient and higher cost," said Robert Atcher, director of the National Isotope Development Center under the U.S. Department of Energy.

About 80 percent of the nuclear medicine procedures rely upon the isotope technetium-99m, which has a "half-life" of just six hours. That means the radioactive substance decays by 50 percent every six hours until it vanishes, which makes it impossible to stockpile.

Half of the entire U.S. supply of that isotope comes from the National Research Universal (NRU) reactor at Chalk River in Ontario, Canada. But the reactor suffered an unexpected shutdown in May 2009, and only just restarted in August 2010.

Shortages get worse

That left a shortfall despite three reactors in Belgium, France and South Africa stepping up their production.

"There still have been times in April, May and July when their schedules were such that there was virtually no material available," Atcher told LiveScience. "There has been a shift to an older isotope for cardiac imaging, but we have exceeded our ability to produce that one as well."

Atcher presented a report on the shortage at the 240th National Meeting of the American Chemical Society held this week.

Supplies became even more strained when the High Flux Reactor in the Netherlands went offline in February 2010.

Shipment problems also affect the U.S. supply, which depends mostly upon foreign sources of medical isotopes and makes just 10 percent to 15 percent of its isotopes domestically. Outside shipments halted after the Sept. 11, 2001, attacks, as well as during the air travel disruptions caused by the eruption of the Icelandic volcano Eyjafjallajokull.

Ripple effects

The shortage has already led to bad effects for nuclear medicine beyond physicians turning to older, more expensive procedures.

For instance, many companies that convert the isotopes for medical applications have ceased to be profitable. Nuclear medicine technologists who typically handle the injections isotopes into patients’ bloodstreams and image patients have also suffered cuts in work hours and layoffs.

A radioactive isotope shortage also threatens activities such as environmental research, oil exploration and regulating nuclear proliferation.

For now, rescuing nuclear medicine will require major changes enabled by the Food & Drug Administration (FDA) and the Centers for Medicare & Medicaid Services (CMS), according to Atcher.

"We need FDA and CMS to enable the expansion of PET (Positron Emission Tomography) imaging by approving radiopharmaceuticals for use, and to agree to reimburse for studies using new probes that are much more powerful in the information that they provide," Atcher said.

This article was reprinted with permission from LiveScience.

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